Metal clad switchgear



Get. 10, 1939. H H RUGG 2,175,854

METAL CLAD SWITCHGEAR Filed Dec. 17, 1937 3 Sheets-Sheet 2 WITNESSES:

Oct. 10, 1939. H. H. RUGG METAL CLAD SWITCHGEAR Filed Dec. 17, 1937 3Sheets-Sheet 3 WITNESSES: XJQMVQ Patented Oct. 10, 1939 UNITED STATESPATENT OFFICE METAL GLAD SWITCHGEAR Pennsylvania Application December17, 1937, Serial N 0. 180,389

8 Claims.

My invention relates, generally, to metal clad switchgear, and, moreparticularly, to metal clad switchgear of the vertical lift type inwhich the breaker unit is removable from the cell or housing in ahorizontal phase.

An object of my invention, generally stated, is to provide a metal cladswitchgear structure which shall be simple and eflicient in operationand which may be readily and economically manufactured and installed.

A more specific object of my invention is to provide for so supporting abreaker unit in a housing that the unit may be inserted into and removedfrom the housing Without the use of bolts or other fastening devices.

Another object of my invention is to provide a simplified means forraising and lowering a circuit breaker unit in a cell structure.

Other objects of the invention will be explained fully hereinafter orwill be apparent to those skilled in the art,

In accordance with one embodiment of the invention the breaker unit israised and lowered in a vertical plane by four motor driven screws, oneof which is located at each corner of the housing. The rear end of thebreaker frame is supported by a cross bar that is disposed between thetwo rear screws and raised and lowered by nuts on these screws,Individual nuts on the front screws engage supports on the breaker framewhich are open at the rear to permit withdrawal of the breaker unit fromthe front of the housing in a horizontal plane without removing anybolts or other fastening devices.

For a fuller understanding of the nature and objects of the invention,reference may be had to the following detailed description, taken inconjunction with the accompanying drawings, in which:

Figure 1 is a view, partially in side elevation and partially insection, of a metal clad switchgear structure embodying my invention;

Fig. 2 is a view, partially in end elevation and partially in section ofthe structure shown in Fig. 1;

Fig. 3 is a view, in side elevation of a portion of the structure,showing the breaker unit resting on a transport truck and partiallyremoved from the housing, and

Fig. 4 is a view, in plan, of the structure shown in Fig. 3,

Referring to the drawings, the apparatus shown comprises a steel cellstructure I enclosed by sheet metal side walls II, end walls I2 and atop wall I3. The structure supports insulator bushings I4 in which aremounted fixed contacts I5 which may be connected to power conductors(not shown), The contacts I5 are adapted to be engaged by disconnectcontacts I6 carried by terminals i! of oil circuit breaker housings I 8,which are suspended from a framework I9 to constitute a circuit breakerunit.

In the present embodiment of the invention, the circuit breaker unitcomprises three separate tanks I8 and is adapted for use in three-phasepower systems. It will be understood that the structure may be readilymodified to be suitable for use in single phase power systems.

In order that the circuit breaker unit may be raised to the positionshown in Figs. 1 and 2, in which the fixed contacts I5 are engaged bythe contacts I6, and lowered to the position shown in Figs. 3 and 4, inwhich the unit may be removed from the cell by means of a transporttruck 2I, a motor driven screw 22 is provided at each corner of thehousing III,

The screws 22 are driven by a motor 23 mounted on a suitable support 24at the rear of the housing I0. The two screws at one side of the housingare driven by a shaft 25 which is connected to the lower ends of thescrews through suitable gearing mechanisms 26, and the two screws at theother side of the housing are driven by a similar shaft 21. The twoshafts 25 and 21 are driven in unison by the motor 23 through acontinuous chain 28 which encircles sprocket wheels 3| and 32 on theshafts 25 and 21, respectively, and a sprocket 33 on the armature shaftof the motor 23, In this manner, all four screws 22 are driven at thesame speed which ensures that the breaker unit will be maintained in alevel position while being raised and lowered. The upper ends of thescrews 22 are supported by suitable bearings 34 disposed at the top ofthe housing III.

In order that the breaker unit may be readily moved into and out of thehousing II] in a horizontal plane and raised and lowered in a verticalplane without removing any bolts or other fastening devices, the rearend of the breaker frame I9 is carried by a cross bar 35, disposedbetween the two rear screws, and the front end is supported by a pair oflugs 36, one of which is secured to each side of the breaker frame I9.The cross bar 35 is raised and lowered by nuts 31 which travel up anddown the rear screws 22 when they are driven by the motor 23, and thelugs 36 are raised and lowered by similar nuts on the front screws. Twospaced dowel pins 38 are provided on top of the cross bar 35 to fit intoholes 39 in the bottom of the breaker frame to maintain its alignmentwhile being raised.

As shown in Figs, 3 and 4, the cross bar 35 remains in the housing whenthe breaker unit is removed from the housing but the lugs 36 are removedwith the breaker frame since they are secured to the frame. The lugs 36are provided with slots 4| for engaging the nuts 31 on the front screws22. The slots 4| are open at the rear to permit the breaker unit to bewithdrawn from the housing without interfering with the screws 22, Thenuts 31 are prevented from turning on the screws 22 by channel guidemembers 42, vertically disposed in the housing 10.

In order that the breaker unit may be lowered directly on the transporttruck 2!, the truck is so constructed that it can be run into thehousing underneath the elevating mechanism. The truck is provided withflanged wheels 43 which run in grooves 44 in the floor of the housing. Ametal plate 45 may be provided at one side of each of the grooves 44 toconstitute rails for the wheels 43.

It will be seen that the breaker unit may be removed from the housing byoperating the motor 23 in the usual manner to lower the nuts 31 on thescrews 22 until the breaker tanks 18 are resting upon the truck 2|. Thenuts 3'! should be lowered sufficiently to disengage the dowel pins 38,on the cross bar 35, from the holes 39 in the bottom of the breakerframe l9 and also to disengage the front nuts 31 from the lugs 36 on theside of the frame 19. The breaker unit can then be withdrawn from thehousing on the truck 2! without interfering with the screws 22 since thelugs 36 are open at the rear, as previously described, and the cross bar35 remains in the housing between the two rear screws 22.

Likewise, the unit can be inserted into the housing by moving the truckinto the cell until its wheels strike stop members 46 disposed on theplates 45, in which position the holes 39 are over the dowel pins 38 andthe lugs 36 are over the front nuts 31. When the breaker unit is in thecorrect position, the motor 23 may be operated in a direction to raisethe nuts 31, thereby elevating the breaker until the contacts l areengaged by the contacts [6. The operation of the motor 23 may becontrolled in any suitable man ner, as by control switches which may belocated at any convenient place.

However, it is desirable to provide a limit switch 41 to stop the motorwhen the breaker unit is raised to the correct position at the top ofthe housing, thereby preventing injury to the elevating mechanism. Asshown, the limit switch 41 may be so disposed in the housing that it isoperated by one of the nuts 31 to stop the motor when the breaker is atthe proper elevation.

It will be noted that breakage of the chain 28 will merely cause thebreaker unit to stop with out injury to the breaker or the elevatingmechanism since all four elevating screws will be stoppedsimultaneously. However, if separate chains were. used to drivedifferent screws, the stopping of part of the screws while the othersremained in operation would result in injury to either the breaker unitor the elevating mechanism, or both.

From the foregoing description, it is apparent that I have provided asimple and eflicient elevating mechanism for circuit breaker apparatuswhich permits the apparatus to be withdrawn from an enclosed cellstructure without removing any bolts or other fastening devices.Furthermore, the possibility of injury to the apparatus or the elevatingmechanism by a failure of a part of the equipment is minimized.

Since numerous changes may be made in the above described constructionand different embodiments of the invention may be made without departingfrom the spirit and scope thereof, it is intended that all mattercontained in the foregoing description or shown in the accompanyingdrawings shall be interpreted as illustrative and not in a limitingsense.

I claim as my invention:

1. Switchgear apparatus comprising a cell structure, a circuit breakerunit movable into and out of the cell in a horizontal plane, a pluralityof screws disposed within the cell for raising and lowering the breakerunit in a vertical plane, gearing mechanisms for driving said screws, amotor for driving the gearing mechanisms, and a continuous chain forconnecting the motor to said gearing mechanisms, whereby all of saidscrews are driven at the same speed through said chain.

2. Switchgear apparatus comprising a cell structure, a circuit breakerunit movable into and out of the cell in a horizontal plane, a pluralityof screws disposed within the cell for raising and lowering the breakerunit in a vertical plane, a pair of horizontally disposed shafts fordriving said screws, a motor for driving said shafts, and a continuouschain for connecting the motor to both of said shafts, whereby all ofsaid screws are driven at the same speed through said chain.

3. Switchgear apparatus comprising a rectangular cell structure, acircuit breaker unit movable into and out of the cell in a horizontalplane, a screw disposed at each corner of the cell for raising andlowering the breaker unit in a vertical plane, a shaft disposed at eachside of the cell for driving tht screws on the side on which the shaftis located, a motor for driving said shafts, and a continuous chain forconnecting the motor to both of said shafts, whereby all of said screwsare driven at the same speed through said chain.

4. Switchgear apparatus comprising a rectangular cell structure, acircuit breaker unit movable into and out of the cell in a horizontalplane, a screw disposed at each corner of the cell for raising andlowering the breaker unit in a vertical plane, means for driving saidscrews at the same speed, means carried by and connecting the screws atthe rear of the cell for supporting the rear end of the breaker unit,and slotted means secured to the breaker unit and cooperating with thescrews at the front of the cell for supporting the front end of thebreaker unit.

5. Switchgear apparatus comprising a rectangular cell structure, acircuit breaker unit movable into and out of the cell in a horizontalplane, a screw disposed at each corner of the cell for raising andlowering the breaker unit in a vertical plane, means for driving saidscrews at the same speed, means horizontally extending between thescrews at the rear of the cell and carried thereby for supporting therear end of the breaker unit, and slotted means secured to the sides ofthe breaker unit and cooperating with the screws at the front of thecell for supporting the front end of the breaker unit.

6. Switchgear apparatus comprising a rectangular cell structure, acircuit breaker unit movable into and out of the cell in a horizontalplane, a screw disposed at each corner of the cell for raising andlowering the breaker unit in a vertical plane, means for driving saidscrews at the same speed, means horizontally extending between thescrews at the rear of the cell and carried thereby for supporting therear end of the breaker unit, and means secured to the sides of thebreaker unit and cooperating with the screws at the front of the cellfor supporting the front end of the breaker unit, said last named meanshaving slots disposed therein for receiving said screws, said slotsbeing open at the rear to permit the breaker unit to be withdrawn fromthe cell.

7. Switchgear apparatus comprising a rectangular cell structure, acircuit breaker unit movable into and out of the cell in a horizontalplane, a screw disposed at each corner of the cell for raising andlowering the breaker unit in a vertical plane, means for driving saidscrews at the same speed, a cross bar disposed between the screws at therear of the cell for supporting the rear end of the breaker unit, a nutdisposed on each of said rear screws for raising and lowering the crossbar, a lug secured to each side of the breaker unit, and a nut disposedon each of said front screws for engaging one of said lugs to raise andlower the front end of the breaker unit, said lugs having slots thereinfor receiving said front screws, said slots being open at the rear topermit the breaker unit to be withdrawn from the cell.

8. Switchgear apparatus comprising a rectangular cell structure, acircuit breaker unit movable into and out of the cell in a horizontalplane, a screw disposed at each corner of the cell for raising andlowering the breaker unit in a vertical plane, means for driving saidscrews at the same speed, a cross bar disposed between the screws at therear of the cell for supporting the rear end of the breaker unit, meanson the cross bar for engaging the breaker unit, a nut disposed on eachof said rear screws for raising and lowering the cross bar, a lugsecured to each side of the breaker unit, a nut disposed on each of saidfront screws for engaging one of said lugs to raise and lower the frontend of the breaker unit, said lugs having slots therein for receivingsaid front screws, said slots being open at the rear to permit thebreaker unit to be withdrawn from the cell, and guide means disposed inthe cell to prevent said nuts from turning on said screws.

HAROLD H. RUGG.

